Smoothing out jagged mesh edge in edit mode
In this case, You could select chunks of your mesh in Edit Mode, and invoke (Header Menu) &gt; Mesh &gt; Convex Hull, followed by X &gt; Limited Dissolve:

But you lose some edges.
One other possible approach, if you need to retopologise, or Convex Hull is not a good starting-point:  somehow make parts of the mesh available to the shipped add-on Loop Tools, and its Curve operator. (Much Slower)
In Edit mode, duplicate off a region with a profile of interest:

and..


F fill, or X &gt; Limited dissolve, convert it to a single non-planar Ngon
To make it available to Loop Tools &gt; Curve, at least, extrude it. This one is inset, too. Select the projecting vertices. A good sign of acceptable topology is that this can be achieved by selecting the first two vertices, and the rest, incrementally, by using CtrlShiftNumpad +
Invoke Loop Tools &gt; Curve on that loop.
Duplicate the loop, or delete the other vertices.


Now, with Snap set to 'To: Vertex' and 'With: Active', snap the fixed profile back on to the original model. Repeat the process with other profiles.
Then you can (Edge Menu) &gt; Bridge Edge Loops reproduce the shapes with better topology.